Automatic suction circulating pump



G. 'FABIG AUTOMATIC SUCTION CIRCULATING PUMP May l2, 1942. l

Filed April 17, 1959 [bye/#0m earg Fa g Patented May.A 12, 1942AUTOMATIC SUCTION CmCULATING PUMP Georg' Fabig, Berlin-Frohnau, GermanyApplication April 17,1939, serial' No. 268,156

In Germany April 21, 1938 2 6 claims. (ci. 10h96) Y This inventionrelates to an automatic suction circulating pump which operates partlyas water ring pump and partly as centrifugal pump, a

vmore favorable efficiency being obtained than in the case of water ringpumps proper. Therefore,` only the sucked-in air and a. small quantityof the sucked-in liquid are forced by means ofthe water ring through thepressure slot lo. cated n ear the wheel hub into the pressure chamber ofthe pump, whereas the main quantity is flung out of the pallet wheel bythe action of centrifugal force and conducted into the pressure chamberpreferably through anouter outlet arranged near the periphery of thewheel. So as to obtain at the same time a large quantitive delivery itis important to force into a suitably arranged reception chamber in thecasing, herein called the pressure channel, the quantity of liquid toVbe delivered by centrifugal eiect, immediately after it has beensucked-in (or after its supplementing quantity has been sucked-inl',that is while it is still within the sector in which vby the centrifugalforce effect is thereby increased.v l

In the accompanying drawing: Fig. 1 shows a side elevation partly insection of a pump accordingto the invention,l which has three pressurestages.

Fig. 2 shows one of these stages on slightlyenlarged scale and insection on line II-II of Fig. 5`is a section according to line V-V ofvFig. 6 through the paddle'wheel and through another construction ofone-half of the casing.

the suction slot is located, and to allow this quanv tity of liquid tocirculate in this channel with the pallet wheel until it reaches4 thepassage lead-v ing to the pressure chamber. Such a construe-4 tion isknown from German Patent No, 618,414, granted to applicant. r Theinvention consists in that symmetrical paddle wheels with continuousside edges are employed. The channel for the liquid conveyed bycentrifugal force effect is provided on the one side, and the channelfor the liquid conveyed by displacing effect is arrangedon the otherside of the paddlewheel in the pump casing. The discharge apertureforthe displaced liquid is separatedfrom the discharge aperture for the`liquid conveyed by centrifugal force effect.

The two channels for the liquid conveyed by centrifugal vforce effectand for the liquid con- 40 veyed by displacer effect extendY practicallyun- `symmetrically the one relative to the other. The course of thechannels depends on-their different manner of operation. Thecross-section of the channel designedfor receiving the circulatingwatering can reduce in the sector of the discharge aperture for theliquid conveyedby c entrifugal force effect. This liquid is therebyl de-Fig.- 6 shows the casing half shown in section in Fig. 5 viewed from theinner side, and

` Fig. 7' is a section lthrough a, portion of this casing half on theline VII- VII of Fig.. 6.

In Fig. 1 a designates' the body forming the suction chamber andb thebody forming the parts f and ;g are provided. The parts c and d enclosethe working space of the stagein which the pallet wheel h rotates. Inthe case of a single stage pump, it is evident that the parts a ande. orand d may be madev as single pieces.

The channel i begins in the sector of the admission port e. Thecross-section-of this chanz nel enlarges in this sector., In the sectorofthe discharge port g of the channel l' for the liquid conveyed bycentrifugal force effect the crosssection 1 reduces4 again, that is, atthis point the water fromthe channel i again enters from the l rsideinto the chambers of-the pallet wheel and flected and the owing outthrough the, discharge aperture is assisted. The channel which takes upthe liquid conveyed by centrifugal force effect may extend in spiralshape, so that the distanceof the channel from the axis ofthe pumpgradthereby assists the outilowof the water `through the port g andpresses a portion of the liquid to be conveyed through the dischargeport f into the next following pump stage or into the, pressure socketb'.

The pressure channel I' for the liquid conveyedv by centrifugal forceeffect begins at m also in the' sector of the admission port e and .hasat its corn-4 menc'ement a shallow depth in axial direction at jcorrespondingly larger radial height. .The liquid current to be conveyedby V.the pallet wheel is therefore in intimate contact .with the edgesof v ually increases. The increase of pressure caused the pallets overtheir entire length: The chanarranged to the direction of ow.

nel lis made in spiral shape so that at its end n it is located chieyoutside the periphery of the pallet wheel. At the same time thecross-sectional shape of the channel changes gradually in such a mannerthat the depth in axial direction increases whereas the radial heightdecreases. This increase in depth in -axial direction need only be up tothe beginning of the outer outlet aperture g, the depth can then becomegradually less in proportion as the liquid is lead oil through thisoutlet.

In this form of construction the reception4 decreases at the endcorresponding to the return movement of the water ring. The radial widthis assumed to be constant in this form of construction, it may, however,vary in the same manner as in the case of the pressure channel l'. Thepallet wheel h, when the water ring chamber is thus constructed, needhave no recesses, that is may have pallets of constant axial width.

It is advisable to provide a recess o in the housing parts c and d bywhich recess the ends of the two channels i and l" are connected acrossthe periphery of the pallet wheel. Thus, an axial pressure is exerted onthe liquid current in the passage l by the bevelled side faces of thechamber i outside the pallet wheel, and this pressure assists thedeection of the liquid at the outlet aperture y.

In the form of construction illustrated in Figs. 5 to 7 the spiral shapeof the pressure channel l' and the gradual reduction in radial widththereof is utilized to enable the outlet aperture g to be The liquidcurrent at the point p passes behind the wall q which closely surroundsthe ends of the ets of the pallet wheel and shuts oil' the portion ofthe working space under suction from that under pressure. 'Ihe pressurechannelr on the side of the housing part d belonging to the pressurechamber is extended in the manner illustrated in dotted lines, so thatthe liquid can pass into the pressure chamber without the necessity tochange its direction of flow. This extension r oi the pressure channelis therefore located `outside its commencement n and on'the other sideof the housing wall. The smooth oiI-ow of the centrifuged liquid isshown particularly clearly in Fig. 7 which illustrates a portion of thehousf ing part d in developed state.

The favorable e'ect of the new construction is proved by the improvementin the degree of efciency of the automatic suction circulating pumps. Anappreciable improvement is already noticeable when merely the pressurechannel is of the spiral shape described. It has been ascertained bymeasuring that with a high percentage air exhaustion in the suction linesuch as was hitherto only attainable with purely water ring pumps,degrees'of emciency of 45% and more can be attained such as have neverhitherto been attainable byautomatic suction circulating pumps.

I claim: 1. Rotary suctio'n pump,` which delivers a portion of thesucked-in liquid by displacement effect and another portion bycentrifugal force,

comprising a pallet rotor with symmetrically formed vanes havingcontinuous side edges, a casing enclosing said rotor and having inletports and outlet ports, the outlet port of the displaced portion ofliquid being separated from the outlet port of the portion delivered bycentrifugal force, a channel for the liquid ring exerting the displacingeect provided in said casing on one side of said vanes, thecross-section of which increases in the sector of the admission port anddecreases again in front of the discharge port for the displaced portionof the liquid, and a passage for the liquid delivered by centrifugalVeifect arranged in said casing on the opposite side of said vanes.

2. Rotary suction pump, which delivers a portion of the sucked-in liquidby displacement effect and another portion by centrifugal force,comprising a pallet rotor with symmetrically formed vanes havingcontinuous side edges, a casing enclosing said rotor and having inletports and outlet ports. the outlet port of the displaced portion ofliquid being separated from the outlet port of the portion delivered bycentrifugal force, a channel for the liquid ring exerting the displacingeffect provided in said casing on one side of said vanes, thecross-section of which increases in the sector of the admission' portand decreases in the sector of the discharge port for the liquidconveyed by centrifugal force, and a passage for the liquid delivered bycentrifugal effect arranged in said casing on the opposite side of saidvanes, said channel and passage extending asymmetrically the one to theother.

3. Rotary suction pump,'which delivers a portion of the sucked-in liquidby displacement effect and another portion by centrifugal force,

comprising a pallet rotor with symmetrically formed vanes havingcontinuous side edges, a casing enclosing said rotor and having inletports and outlet ports, the outlet port of the displaced portionofliquid being separated from the outlet port of the portion deliveredby centrifugal force, a. channel for the liquid ring exerting thedisplacing eiect provided in said casing on one side oi' said vanes thecross-section of said channel decreases in the sector of the dischargeport of the liquid conveyed by centrifugal force, and a passage for theliquid delivered by centrifugal effect arranged insaid casing on theopposite side of said vanes, said channel and passage extendingasymmetrically the one to the other.

4. Rotary suction pump, which delivers a portion of the sucked-in liquidby displacement effect and another portion by centrifugal force,comprising a pallet rotor with symmetrically formed vanes havingcontinuous side edges, a casing enclosing said rotor and having inletports and outlet ports, the outlet port of the displaced portion ofliquid being separated from the ,outlet port of the portion delivered bycentrifugal force, a channel for the liquid ring exerting the displacingeifect provided in said casing on one side of said vanes, thecross-section of which increases in the sector of the admission port anddecreases again in the sector of the discharge port for the displacedportion of the liquid, and a passage for the liquid delivered bycentrifugal effect arranged in `said casing on the opposite side of saidvanes, said passage having at its beginning little axial depth but greatradial height, and changing its cross-section shape in the direction ofrotation so that the axial depth increases and the radial heightdecreases.

5. Rotary suction pump, which delivers a porsage for the liquiddelivered by centrifugal effect tion of the sucked-in liquid bydisplacement effect and another portion by centrifugal force,

comprising a pallet rotor with symmetrically that the distance from theaxis slowly arranged in said casing on the opposite side of said vanes,said passage being spiral-shaped so increases in the direction o!rotation.

6. Rotary suction pump as specied in claim 1,. in which the outlet portof said passage is arranged so that theliquid is discharged in thevplane of rotation in tangential direction,l and a channel is providedin said casing and connected to said outlet port, vthe radial distanceof this channel from the axis ofthe pump being greater than the distanceof said passage.

GEoRG FABIG.

